NEW YORK — Peter Thum opens a bag and begins placing its contents on a small table. The contrast is jarring as the surface slowly fills with a mix of snub-nosed revolvers and finely wrought jewelry. Pieces of the former were used to create the latter, part of the entrepreneur's mission to help get guns out of circulation.

"Guns are a huge problem," but people are leery of talking about it, says Thum (pronounced Thoom). "I wanted to give people who are on the sidelines a way of getting in the game."

Thum, 46, who launched Ethos Water a decade back and sold it to Starbucks in 2005, has two start-ups that turn firearms into fashion.

Fonderie 47 takes AK-47 assault rifles used in African conflicts and turns them into jewelry that costs $8,000 to $150,000, conjured by the likes of designer Philip Crangi. LinkedIn founder Reid Hoffman will soon take delivery on a Fonderie watch worth $350,000.

Liberty United is aiming for a broader market. It uses handguns confiscated by police departments in three U.S. cities as source metal for jewelry priced at $80 to $1,600. Both companies have online stores, but Liberty United wares may hit select retailers later in the year.

Each Fonderie item guarantees the destruction of a certain number of guns ("Reid's watch will see that 1,000 African AKs are physically destroyed," says Thum), while 25% of Liberty proceeds go to police and community organizations around the U.S. — including his gun-donor hubs of Philadelphia, Syracuse and Newburgh, N.Y. — that work to get rid of firearms.

"It's surprising that in the oldest constitutional democracy with such great wealth that we accept a very high level of gun violence," says Thum, who delivers his words with the calm resolution of the fact-fueled management consultant he once was. "The acceptance of the issue allows for its perpetuation."

Meeting at the offices of foundry City Casting, Thum eagerly checks on the molten transformation of gunmetal into Liberty United rings and bracelets shaped like encircled railroad spikes. As with anything Thum does, there's meaning behind the motif.

"The golden spike was the symbol of the completion of the transcontinental railroad, used to mark where the western and eastern lines met (in Utah in 1869)," he says. "So with our jewelry, it's meant to symbolize turning these guns into something exemplary of American progress."

He means that literally: Each Liberty piece is stamped with one or more serial numbers of guns that were eliminated in the process of making the jewelry.

The idea for Fonderie was hatched during one of many trips to Africa to check on water projects funded by the proceeds of Ethos. Thum was surrounded by people desperate for water, who in turn were surrounded by people wielding guns.

Thum immediately identified one of many problems associated with getting rid of conflict weapons.

"The people who guard the guns that are going to be destroyed make a few hundred dollars a year, but often they're not paid and yet they are literally guarding $100 bills, because that's what each AK is worth, if not more," he says. "So the organizations need money just to do the jobs they do. I felt I could help."

Bringing the program stateside with Liberty United was the result of urging from Thum's wife, actress Cara Buono. "We'd just had a baby girl (who now is 18 months old) and she felt it was important to help out where we lived," he says.

Buono, who grew up in the Bronx, says she still has memories of people being shot in her neighborhood. "Becoming parents made it a simple choice," says the Sopranos and Mad Men actress. "It was instinctive given how prevalent the problem is here."

Besides, she adds, "Everyone loves things that are affordable, beautiful and also have meaning. It just makes you feel good."

Although Buono admits she is a biased observer, she says her husband's motivation for starting both companies stems from "his innate feeling that he has a responsibility to make a difference in the world."

Thum has chosen a particularly thorny issue, given that guns provoke passionate volleys from those who defend their right to bear arms and others who see such weapons as having an inordinately high toll on civil life.

"Work like (Thum's) is an important part of the solution as it asks for the genuine engagement of the American public," says Dan Gross, president of the Brady Campaign to Prevent Gun Violence.

"Fashion and the arts have always played an important role in bringing tough issues into the popular culture, whether that's the environment, AIDS or animal rights," says Gross, who notes that 30,000 Americans are killed by guns annually. "We need to take this beyond political dialogue, and Thum is representative of that."

Thum doesn't see himself or his start-ups in such glorified terms. Instead, he feels he's simply spotted an opportunity to simultaneously do good for society and himself.

It's the same instinct that led the onetime Gallo wine employee turned McKinsey & Co. consultant to spot a hole in the market when he consulted to bottled water giants. He realized "people were willing to pay a premium for water from somewhere else with nice packaging, so maybe they would pay for water that helped other people."

In 2001, he wrote a business plan for Ethos, which took some proceeds to help fund water projects globally, and by 2005 Starbucks came knocking. He had wanted to keep the company, "but I realized fast that in order to create a lasting brand and distribute on that sort of huge level I couldn't do it on my own."

With both Fonderie 47 and Liberty United, his aim is, in fact, to create another pair of lasting brands that happen to also have an altruistic bent.

"It's important to begin the (start-up) journey motivated by the desire to tackle a serious problem, and then you need to operate like anyone else and try and win in that market, whether it's bottled water or watches," he says. "Fads are easy. But if you want to build a real company you have to produce something that makes people happy inside. Hopefully, I am."

Where were you hit with the cost of gun violence? "We had funded a water project (through Ethos, his first company) in Kenya, and we ran into people with guns. That's frightening, but what you quickly realize is that after spending $1 million on a (water) project, it can all be put in jeopardy by armed conflict. Guns end up representing a significant cost of just putting people on the ground there safely."

Can companies on a mission enjoy long-term growth? "If you have a mission to solve a social problem and designers with really creative ideas, when those things meet they both have to be exceptional if you want to create another vector to guarantee long-term success. Otherwise, it winds up just looking like a fundraising campaign."

What's your advice for anyone starting a company? "First, I'd say that the best time to start a business is today. Any reason not to do it is just a roadblock in your head. If you fail, it just teaches you how to pivot to something else. And second, carefully plot out what you think you'll need to achieve your goals, then triple the amount of time and money."

USA TODAY's Change Agents series highlights innovators and entrepreneurs looking to change business and culture with their vision. E-mail Marco della Cava at mdellacava@usatoday.com. Follow him on Twitter:@marcodellacava.

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